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This papper is about the use of biopolymer of polyvinyl alcohol (PVA) as a coat of different fertilizer granules (Azafoska 16:16:16 and Yara Kristalon 19:19:19) as a core material in presence of nitric acid. The biodegradable polymer layer provides uniform diffusion of minerals into the soil as the PVA shell decays. Scanning Electron Microscope (SEM) and Energy – Dispersive X-ray spectroscopy (EDX - 3600) were carried out for the characterization of bio-modified materials. The agrochemical changes of the soil in terms of macro-and microelements were also determined.

The present work describes direct one-pot synthesis of the two novel amino acids – boron-dipyrromethene (BODIPY) conjugates with histidine and tyrosine residues bound to fluorophore via amino group. The synthesized compounds were fully characterized by means of 1H and 11B nuclear magnetic resonance spectroscopy, infrared spectroscopy, time-of-flight mass spectrometry with matrix-activated laser desorption / ionization. All the data are in accordance with the proposed structures. The amino acids – BODIPY conjugates under study were investigated by means of absorbance and fluorescence spectroscopy. Absorption and emission spectra of the compounds in dimethyl sulfoxide (DMSO) – buffer solution (BS) mixture (1:1) were obtained. Moreover, a number of photophysical characteristics of the conjugates, namely: relative fluorescence quantum yield, molar extinction coefficient, relative fluorescence lifetime, radiative and non-radiative rate constants were calulated. 3D fluorescence spectra of the compounds in DMSO – BS mixture (1:1) were obtained. Absorption and emission titration of the compounds was carried out. The results of the titration allowed us to confirm additionally a stoichiometric composition of the conjugates. Quantum chemical analysis of structural and spectral properties of the compounds in a ground state was carried out. The results of quantum chemical calculations gave an insight to a nature of the BODIPY – amino acid interactions in the conjugates. Besides, the synthesized amino acids – BODIPY conjugates are found to be highly soluble in polar solvents. Thus, a range of unique properties of the objects of the present research enables us to use them for visualization of bioactive macromolecules as well as biochemical processes in living cells.

Four BODIPY (boron-dipyrrin) dyes with various condensed aromatic moieties (phenyl, naphthyl, anthryl and pyrenyl) as 8-substituents were chosen and their supramolecular organization and properties in Langmuir–Schaefer (LS) films with different numbers of layers were investigated. The spectral characteristics of the dyes in LS-films and solution and the structure of the films were examined. The BODIPY substituent structure influences the character of the intermolecular interactions of the dyes in LS-films. The phenyl-substituted compound was found to form excimers with a long wavelength fluorescence peak at 582 nm upon the layer number increase, yet only minor bathochromic shifts of the peak position were observed for the films of the other investigated compounds. Moreover, unlike in liquid solutions, the dyes in LS-films were not found to exhibit solvatochromic properties. All of the compounds (except anthryl-substituted) were found to retain fluorescence in solid films. Transfer of films from a floating monolayer was indicated by further material analysis: the measured average periodicity corresponds to a single-layer structure of BODIPY molecules located parallel to the surface with an interplanar distance of d = 0.3 nm. The obtained results broaden the prospects of BODIPY based thin film material applications, denoting versatile modification routes leading to increased fluorescence, tunable excimer formation equilibrium and crystallinity.

This review summarizes the results of research published in recent decades on the main directions in the functionalization of fibrous materials using surface modification. Methods for thepreliminary activation of the surface of fibrous materials are described, allowing increasing the adhesion of modifiers. The features of the formation of functionalizing coatings on fibrous materials in comparison with other substrates are analyzed. Some specific methods for evaluating the effectiveness of the surface modification inherent in fibrous materials are considered. Particular attention is paid to giving fibrous materials antimicrobial properties, photoactivity, the ability to protect against ultraviolet radiation, and hydrophobicity.

We report the synthesis, purification and identification of a new derived class of BODIPY - of naphtho-fused BODIPY analogue, 8-(3,5-dimethylphenyl)-4,4-difluoro-4-bora-3a,4a-diaza-dinapht-[1,2b][1,2c]-s-indacene. A detailed method for obtaining the compound was given. The structure was confirmed by nuclear magnetic resonance spectroscopy, infrared spectroscopy and mass spectrometry. Electronic absorption and fluorescence spectra were obtained in solvents of different nature. The effect of solvent nature on the positions of absorption and fluorescence peaks and Stokes shift has been studied. It has been shown that the nature of the solvent has a significant effect on the fluorescence intensity and does not significantly effect the position of the absorption peaks. The photophysical characteristics of the compound were compared with known alkylated analogues. It is shown that the expansion of the electronic system leads to a bathochromic shift in the electronic absorption and fluorescence spectra. Quantum-chemical calculations of the electronic absorption and fluorescence spectra were carried out using the TDDFT (time dependent density functional theory) method. The influence of the extended π-electron system on the position and character of the absorption and fluorescence spectra was studied. It is shown that the presence of naphthalene fragments conjugated with the BODIPY core leads to a bathochromic shift of the absorption and fluorescence bands, as well as a partial change in the character of the spectra. The energy levels and electronic structure of the FMOs with the TDDFT method were calculated. The calculated data are in good agreement with the results obtained by experimental methods. The results obtained, in turn, are consistent with the results obtained earlier by our scientific group. Compounds that possess such properties are especially important and could be used in such practical applications as photovoltaics, photodynamic therapy of oncological diseases and as agents for visualization of biomolecules.

Boron dipyrrins (Bodipy) are unique complexes occupying an intermediate position between classical coordination and organometallic compounds. The enormous interest of researchers from all over the world to the compounds of this class has by now provided an endless stream of publications that requires generalization. Existing reviews and original publications do not fully cover the structural diversity of Bodipy and their possible applications in engineering, medicine, analytical chemistry, optics, photonics, etc. In this paper, w e present the results, mainly of our own research, which for the first time allowed us to establish the physicochemical principles of the formation of Bodipy (the reasons for the low rates of complexation of ligands with boron trifluoride), changes in the spectral and photophysical properties of alkylated Bodipy complexes with the separation of contributions from universal and specific solvation, and examples of functionalization of inorganic and organic polymer materials based on Bodipy of different structures. Examples of the current team’s Bodipy research in different practical areas are presented.

Mineral fertilisers such as nitrous, phosphorous and potassium (NPK –usually called macro elements) are one of the most significant products in agricultural industry. By providing nutrients to the plants, they play an important role in the process of regulating the acidity (pH) and the fertility of the soil and all it leads to increase the crops growth [6].

The spectral characteristics of a compound representing a new class of organic luminescent materials—dipyrrin oxophosphoryl complex (PODIPY)—in organic solvents and thin films have been investigated. The compound under study exhibits high-intensity fluorescence in solutions, which is preserved when passing to thin films obtained by layer-by-layer deposition onto a substrate using the Langmuir–Schaeffer technique. PODIPY is characterized by has bright solvatochromic fluorescence, which is related to the redistribution of the intensities of absorption and fluorescence bands and their shift. This effect originates from the specific solvation of PODIPY with partition of the oxygen atoms of oxophosphoryl group. A transition from solutions to films and an increase in the number of transfers lead to the fluorescence quenching without the formation of G aggregates in the film.

Here we report recent studies of pH and polarity fluorescent molecular sensorics involving range of 4-bora-3a,4a-diaza-s-indacene (BODIPY) derivatives. Photophysical characteristics of the dyes were investigated in liquid solutions and in bulk materials, doped to sol-gel silicon dioxide (pure and with surface modifiers), polymethylmethacrylate (PMMA), polysulfone (PSU) and polyvinyl chloride (PVC) matrices. Investigated compounds were shown to be effective fluorescent probes for precise evaluation of H+ concentration in a broad range of input values (pH 2–12). Factors affecting accuracy of the measurements in solvents and matrices of a different nature are discussed. Finally, Catalan linear regression is introduced as a potential approach for discrimination of solvent polarity effects from acidity.

The review is focused on the recent advances devoted to the diversity of the structures of a number of fluorescent dyes, in particular, dipyrrin complexes of boron – bodipy, their derivatives, analogs and related organic luminophores obtained on the basis of preorganization principles and directed molecular design. The properties of these dyes found in modern materials and acting either as independent preorganized molecules or as a part of complex molecular assemblies obtained by means of self-assembly and self-organization are being discussed. The possibilities of using fluorescent techniques and realizing the potential of optically active materials as high-performance sensors of self-assembly processes were also shown. The obtaining features and spectral characteristics of ionic and coordinate self-assemblies, including individual preorganized fluorophores, supramolecular gels, and polymers, as well as various nanomaterials based on the principles of supramolecular chemistry are being considered. The objective of this review is to show the relationship between unique properties of preorganized fluorophores and related dye-contained systems and their advantages in influencing on/taking part in supramolecular self-assemblies with a further design of new functionalized nano- and micro-sized objects and high-tech materials. Applications of fluorescent technics and optically active materials are also being discussed.

BODIPY dyes possess favorable optical properties for a variety of applications including in vivo and in vitro diagnostics. However, their utilization might be limited by their water insolubility and incompatibility with chemical modifications, resulting in low aggregation stability. Here, we outline the route for addressing this issue. We have demonstrated two approaches, based on dye entrapment in micellar coordination clusters (MCCs); this provides a general solution for water solubility as well as aggregation stability of the seven BODIPY derivatives. These derivatives have various bulky aromatic substituents in the 2,3,5,6- and meso-positions and can rotate relative to a dipyrrin core, which also provides molecular rotor properties. The molecular structural features and the presence of aromatic groups allows BODIPY dyes to be used as "supporting molecules", thus promoting micelle-micelle interaction and micellar network stabilization. In the second approach, self-micellization, following BODIPY use, leads to MCC formation without the use of any mediators, including chelators and/or metal ions. In both approaches, BODIPY exhibits an excellent optical response, at a concentration beyond its solubilization limit in aqueous media and without undesired crystallization. The suggested approaches represent systems used to encapsulate BODIPY in a capsule-based surfactant environment, enabling one to track the aggregation of BODIPY; these approaches represent an alternative system to study and apply BODIPY's molecular rotor properties. The stabilized compounds, i.e., the BODIPY-loaded MCCs, provide a unique feature of permeability to hydrophilic ligand-switching proteins such as BSA; they exhibit a bright "turn-on" fluorescence signal within the clusters via macromolecular complexation, thus expanding the possibilities of water-soluble BODIPY-loaded MCCs utilization for functional indicators.

The design of cargo carriers with high biocompatibility, unique morphological characteristics, and capability of strong bonding of fluorescent dye is highly important for the development of a platform for smart imaging and diagnostics. In this paper, BODIPY-doped silica nanoparticles were prepared through a &ldquo, one-pot&rdquo, soft-template method using a sol-gel process. Several sol-gel precursors have been used in sol-gel synthesis in the presence of soft-template to obtain the silica-based materials with the most appropriate morphological features for the immobilization of BODIPY molecules. Obtained silica particles have been shown to be non-cytotoxic and can be effectively internalized into the cervical cancer cell line (HeLa). The described method of synthesis allows us to obtain silica-based carriers with an immobilized fluorescent dye that provide the possibility for real-time imaging and detection of these carriers.

The article describes synthesis of aminoorgano-functionalized silica as a perspective material for catalysis application. The amino groups have electron donor properties valuable for metal chemical state of palladium. So presence of electron donor groups is important for increasing of catalysts stability. The research is devoted to investigation of silica amino-modified support influence on activity and stability of palladium species in 4-nitroaniline hydrogenation process. A series of catalysts with different supports such as SiO2, SiO2-C3H6-NH2 (amino-functionalized silica), γ-Al2O3 and activated carbon were studied. The catalytic activity was studied in the hydrogenation of 4-nitroaniline to 1,4-phenylenediamine. The catalysts were characterized by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and pulse chemisorption of hydrogen. The 5 wt. % Pd/SiO2-C3H6-NH2 catalyst exhibited the highest catalytic activity for 4-nitroaniline hydrogenation with 100% conversion and 99% selectivity with respect to 1,4-phenylenediamine.

The article describes the synthesis of aminoorgano-functionalized silica as a prospective material for catalysis application. The amino groups have electron donor properties which are valuable for the metal chemical state of palladium. Therefore, the presence of electron donor groups is important for increasing catalysts&rsquo, stability. The research is devoted to the investigation of silica amino-modified support influence on the activity and stability of palladium species in 4-nitroaniline hydrogenation process. A series of catalysts with different supports such as SiO2, SiO2-C3H6-NH2 (amino-functionalized silica), &gamma, Al2O3 and activated carbon were studied. The catalytic activity was studied in the hydrogenation of 4-nitroaniline to 1,4-phenylenediamine. The catalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and chemisorption of hydrogen by the pulse technique. The 5 wt.% Pd/SiO2-C3H6-NH2 catalyst exhibited the highest catalytic activity for 4-nitroaniline hydrogenation with 100% conversion and 99% selectivity with respect to 1,4-phenylenediamine.

New micellar coordination clusters (MCCs) were prepared by the introduction of a hydrophobic chelator onto the interface of nonionic surfactant Triton X-114 followed by “crosslinking” of the structures by metal ions. Their resistance to changes in ionic strength, pH of the solution, and temperature was investigated. Regularities in the interaction of MCCs with α-, β-, and γ-cyclodextrins (CD) were revealed. It was shown that the variation of the type and concentration of CD allowed one to control the mechanism of MCC synthesis and to affect their stability. The involvement of molecular modeling (molecular docking) made possible to elucidate the most energetically favorable structures of complexes of CD with components of MCCs.

Boron dipyrrin (BODIPY) dyes serve as perspective fluorescent sensors and probes in a vast range of biochemical and medical applications. Thus, mechanisms of interaction with biomolecules and accompanying spectral behavior of BODIPY are of major interest for fundamental science and practical applications. 8-aryl BODIPY derivatives were found to have high fluorescent respond upon the protein addition. Investigation of the interaction between the series of BODIPY complexes and Bovine Serum Albumin (BSA) using ultraviolet-visible (UV-vis) absorption, fluorescence spectroscopy under simulated physiological conditions (pH 7.4) and molecular docking methods was performed. The results of fluorescence spectroscopy indicated that the fluorescence of hydrophobic BODIPY dyes substantially increases in the presence of BSA. The prospected reason is binding of the dye to the BSA hydrophobic cavities in the subdomain IIA. Aromatic moiety size increase causes shifting of the interaction driving force from mostly non-specific to the π-stacking. Among all probes, the 8-phenyl substituted dye showed the highest sensitivity and the quantitative fluorescent response for BSA in aqueous solution. BODIPY with 8-phenyl substituent or analogs therefore could be used as protein surface polarity sensors, at the same time all of the investigated dyes with bulky aromatic groups could be used as hydrophobic molecule tags and markers for bioimaging tasks.

Modern approaches to the production of new materials require the improvement of synthesis techniques towards simplifying the processes of their preparation and reducing the number of stages. Thus, in this study, one-stage synthesis of organomodified silica materials is developed using a special surfactant—dodecyldimethylamin N-oxide (DDAO). The peculiarity of this approach is that there is no need for heat treatment of the material, since DDAO is removed by washing in alcohol. Amino-, mercapto-, methyl-, and phenyl-modified silicas were synthesized using this method. The SEM images showed the morphology of all the obtained materials is close, all particles are spherical, and the diameter of individual particles is about 500 nm. Palladium particles were precipitated on these supports, then the experiments were carried out to study the catalytic activity of these materials in a model reaction of nitroaniline reduction. The phenyl modified matrix-based materials showed very low activity. This is due to the fact that the support and the substrate contain aromatic fragments, thus, hydrophobic interactions arise between them, which complicates the diffusion of the products. The leader is a matrix with an amino fragment, which is associated with its electron-donor effect. The XPS method revealed the amount of fixed palladium, as well as the binding energy shifts, which are 0.68 eV for 5% Pd/SiO2–C6H5, 0.56 eV for 5% Pd/SiO2–C3H6–NH2, 0.26 eV for 5% Pd/SiO2–CH3, and 0.13 eV for 5% Pd/SiO2.

In the present study four BODIPY (boron dipyrromethene: 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) dyes with π-extended substituents in C-8 position were investigated in solvents and polymer mediums. High aggregation degree was observed for the dyes in the solid state. Association and twisted intramolecular charge transfer processes were found to affect the spectral properties of the compounds causing bathochromic shifts in absorption and fluorescence spectra. The extension of substituent π-conjugation gains molecular association evoked presumably by π-π interaction between the substituents of the adjacent molecules. Photostability of the complexes in different forms was analyzed and the distorted form stabilized by polymer matrix was found to be the most stable. The substituent nature did not affect strongly the photostability of dyes. Displacement of monomer-associate equilibrium in hybrid materials with polymethylmethacrylate and poly(9-vinylcarbazole) was exploited for tuning spectral characteristics of the materials. Two dyes readily forming aggregates at the lowest concentrations were applied for the fabrication of organic light-emitting diodes. The fabricated devices exhibited electroluminescence in the appropriate spectral ranges with moderate efficiency.

The synthesis of multifunctional nano-sized materials is leading to the rapid development of key application, including improved drug delivery, bioimaging and protein separation. In this work, magnetic silica particles modified with novel guanidine containing co-polymers were manufactured via sol-gel method. To evaluate the chemical composition of our prepared samples, FT-IR spectroscopy and thermogravimetry were conducted. Scanning electron microscopy was used in order to investigate the morphology of final products after modification by guanidine containing co-polymers and iron nanoparticles. In addition, the surface of polymer-silica composites was functionalized by the novel bilirubin-inducible fluorescent protein UnaG. In an aqueous bilirubin solution, the silica particles decorated with the polymer-UnaG have showed bright fluorescence. Synthesis and characterization of these hybrid materials allow developing of new multifunctional nano-sized materials, which will be used for detection and separation of bilirubin, a lipophilic heme catabolite that is a clinical diagnostic for liver function.

An interaction between 5,10,15,20-tetrakis-(N-methyl-x-pyridyl)porphyrins, x=2; 4 (TMPyPs) with bovine serum albumin (BSA) and its bilirubin (BR) complex was investigated by UV-Viz and fluorescence spectroscopy under imitated physiological conditions involving molecular docking studies. The parameters of forming intermolecular complexes (binding constants, quenching rate constants, quenching sphere radius etc.) were determined. It was showed that the interaction between proteins and TMPyPs occurs via static quenching of protein fluorescence and has predominantly hydrophobic and electrostatic character. It was revealed that obtained complexes are relatively stable, but in the case of TMPyP4 binding with proteins occurs better than TMPyP2. Nevertheless, both TMPyPs have better binding ability with free protein compared to BRBSA at the same time. The influence of TMPyPs on the conformational changes in protein molecules was studied using synchronous fluorescence spectroscopy. It was found that there is no competition of BR with TMPyPs for binging sites on protein molecule and BR displacement does not occur. Molecular docking calculations have showed that TMPyPs can bind with albumin via tryptophan residue in the hydrophilic binding site of protein molecule but it is not one possible interaction way.

The results of research on the correlation between molecular structure and spectral luminescent and photophysical properties for a new class of dyes and luminophores based on dipyrrins, bis(dipyrrins), and their coordination compounds in different media are summarized. The new perspective applications of dipyrrin dyes and luminophores as fluorescent sensors for measuring the polarity, viscosity, and temperature of the medium and highly sensitive and selective fluorescent “off-on” chemosensors for detecting Zn2+, Cd2+, and Hg2+ cations in weakly polar and nonpolar organic solvents and biological systems are discussed.

Two boron-dipyrrin (BODIPY) based dyes with dimethylaminophenyl and carboxyphenyl substituents in 8-position of dipyrrin ligand have been synthesized and characterized. Photophysical and spectral properties of the obtained compounds have been investigated in water-ethanol mixture and water-cyclohexane system with variation of pH values. The equilibria constants of the compounds were identified by classical methods of acid-base titration. BODIPY bearing dimethylaminophenyl and carboxyphenyl subunits show deprotonation/protonation dependent fluorescence off/on-switching. The change of the emission could be mechanistically explained by a PET (photoinduced electron transfer) from the 8-substituent to the fluorophore. The present study demonstrates that BODIPY-based fluorescent sensors can be used to measure the pH in the range of 2-13 extending the scope of BODIPY dyes available as pH-indicators. Investigated compounds demonstrate weak dye-dye interaction allowing their cooperative usage as indicators.

Four boron-dipyrrine (BODIPY) based dyes with π-extended substituents in 8-position of dipyrrin ligand have been synthesized and characterized. Photophysical properties of the obtained compounds have been investigated in different individual solvents. Deposits of solvent polarity and viscosity were evaluated. BODIPY with 8-biphenyl substituent was found to be the fluorescent molecular rotor in contrast to more extended substituents. The complex nature of solvent-solute interactions leads to the poor applicability of standard multiparameter approaches to BODIPY solvatochromic properties. Fluorescence intensity was found to increase in case of solvent polarity growth, it is not typical for BODIPY. Taking that into account the BODIPY with π-extended substituents could be used for fluorescence viscosity measurements, and as the fluorescent media polarity indicators in analytical chemistry and biochemistry.

Hybrid materials with Co(II) phthalocyanine immobilized on organically modified silica matrices were obtained. Morphological characteristics of obtained materials were tested by scanning electron and atomic force microscopy techniques and laser diffraction analysis. Covalent immobilization of catalyst was proved by IR spectroscopy data concerning position and intensity of characteristic vibrations for matrix and phthalocyanine. Synthesized materials were evaluated as catalysts for the oxidation of RSH compounds under the temperature and pH variation. Reaction rate constants and activation parameters were estimated. The value of pH about 10 was found to be optimal for the diethyldithiocarbamate oxidation in the presence of studied catalysts. The changing of the limiting step from kinetic to diffusion was observed at 303.15 K for hybrids with mercaptoalkyl and aminoalkyl substituted matrices.

Silicon dioxide thin films with organic fluorescent dyes with different amount of matrix layers were prepared by sol–gel spin coating and dripping technique, synthetic and subsequent treatment parameters were proposed for obtaining materials with high homogeneity and dye stability. The structural, morphological and optical properties of obtained materials have been studied by X-ray diffraction, atomic force microscopy and ultraviolet–visible spectroscopy. Immobilisation of the dye increases the degree of film amorphousness. Immobilisation greatly affects the spectral properties of coumarin 6 and BODIPY due to the dye protonation by acid catalyst, this effect is reversible in case of coumarin 6. Rhodamine 6G spectral characteristics are not influenced by immobilisation. In the hybrid materials monomeric form of the dyes retained at higher concentration compared with solutions. Dye immobilisation was found to increase dyes photostability.

Improving the profitability of the crop industry is associated with the introduction of adapted innovative solutions, including in the field of plant nutrition. Existing scientific achievements in the fertilizer system make it possible to achieve a solution to a set of interrelated tasks: increasing the responsiveness of cultivated plants to the fertilizers used, improving agrochemical and agroecological soil parameters and limiting the outstripping growth of costs for the plant nutrition system.

This paper illustrates the change of coating process reaction from a batch (or semi-batch) into continuous flow (V-star), where the core material consists of NPK macro-elements (16:16:16) and layer is a biodegradable polyvinyl alcohol. Moreover, an additive role of this project is to explore the parameters’ changes of nitrogen, in the soil after application of fertilizer coated with a biopolymer. Besides, the application results of coated biodegradable fertilizer on a virus free (in Vitro) rootstock VSL-2 plant biometrics. The biodegradability results of the coated nitrogen, phosphorous and potassium (NPK) fertilizer (Azafoska) demonstrate strongly dependence on the core material used.

Non-ionic surfactants have raised a considerable interest for solubilization, encapsulation, permeabilization and controlled release of various compounds due to their unique physicochemical properties. Nevertheless, it is still challenging to create convenient self-assembled multifunctional materials with high solubilization and encapsulation capacities by preserving their advanced capabilities to protect loaded cargos without altering their characteristics. In this work, we present an extended concept of micellar clusters (MCs) formation based on partial entrapment and stabilization of chelate ligands by hydrophobic forces found on the non-ionic surfactant micelle interface of the Triton-X family (TX-100/TX-114), followed by subsequent complexation of the preformed structures either by metal ions or a supporting chelator. The formation aspects, inner structure and the role of external factors such as the addition of competitive ligands have been extensively studied. MCs loaded by hydrophobic fluorescent compounds with high encapsulation efficiency demonstrate an excellent optical response in aqueous media without crystallization as well as sufficient increase in solubility of toxic hydrophobic compounds such as bilirubin (>50 times compared to pure surfactants). Furthermore, Triton-X-based MCs provide a unique feature of selective permeability to hydrophilic ligand-switching proteins such as UnaG and BSA demonstrating bright “turn-on” fluorescence signal either inside the cluster or on its interface via complexation. The proposed strategies allowed us to successfully encapsulate and visualize a newly synthesized, highly hydrophobic anticancer PTR-58-CLB-CAMP peptide drug, while MCs loaded by the drug exhibit a considerable antitumor activity against HeLa cells.

Guanidine containing polymers were applied to prepare polymer coated silica particles via a sol–gel method as potential candidates for drug encapsulation. Here, we used four types of grafted polymers for surface modification. The grafting amount was evaluated by thermogravimetric and elemental analysis and was in 18–34% range. Also polymer coated silica particles were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry and high resolution electron microscopy. The effect of grafted polymers on particle properties and pH-response has been reported. Anionic (sulfasalazine) and cationic (doxorubicin) drugs were effectively loaded into polymer coated silicas. The drug loading and drug release were pH dependent and affected by the nature of grafted polymer and its content. The properties revealed for investigated system have shown promising results for drug delivery with pH controllable drug release.

The development and design of adsorbents with high adsorption performance is the actual aim for successful toxin removal. In this work, we report the performance of new guanidine-containing polymers as a shell orientated around silica particles with following application for effective bilirubin removal. To evaluate polymer-shell modification, Fourier transform infrared spectroscopy and high-resolution electron microscopy were performed. Changes in surface morphology of polymer-coated silicas were detected. It was shown that polymeric shell completely covers silica surface. The grafting amount was evaluated by thermogravimetric and was in 18–34 % range. Incorporation of guanidine containing polymers into silica matrix leads to the great increase in adsorption capacity According to the Langmuir model, the maximum adsorption capacity for bilirubin was 43.47 mg/g. We also demonstrated that prepared polymer-coated silicas could well adsorb bilirubin from the bilirubin-albumin solution at low concentration of albumin. Therefore, this study revealed that guanidine-containing polymers have great potential to serve as effective agents for improving of the adsorbent for bilirubin removal.

Hybrid-silica materials containing octyl, phenyl and urea-propyl functional groups were reported. These functionalized silicas were prepared by a via one-pot synthesis method through co-condensation of tetraethyl ortosilicate with organosilanes co-precursors. The obtained materials were analyzed by a number of techniques including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction pattern and nitrogen sorption measurement. The main elements: morphology and surface properties of the final products that are basically dependent on the type and the quantity of functional-containing groups were fully discussed. The adsorption properties of the modified silicas were investigated against bilirubin in aqueous solution at pH 7.4, the effect of time was studied as well. The modified silicas showed a greatly increasing of adsorption capacity for bilirubin compared to pure amorphous silica. The results indicate that the type of functional-containing groups and surface properties affect the adsorption behavior. These materials show a potential application as effective adsorbents for bilirubin removal.

Polyvinylpyrrolidone (PVP) modified silica coated with albumin as host matrices for bilirubin removal were synthesized through sol–gel method. Such materials were characterized by scanning electron microscopy, nitrogen adsorption, Fourier transform spectroscopy and elemental analysis. It was shown that PVP grafted onto silica provides strong and high immobilization of BSA in comparison with pure silica. These modified silicas with different content of BSA were used to study bilirubin adsorption from the bilirubin–phosphate solutions (pH 7.4). The effect of time, ionic strength and concentration on the bilirubin adsorption were investigated as well. The results demonstrate that the adsorption capacity of tested samples increases after surface modification. The maximum adsorption capacity for bilirubin was 2.82 mg/g.

The new hybrid materials containing metal complexes of phthalocyanines with variations in substituent nature were synthesized using the sol–gel technology. Phthalocyanines were covalently immobilized in the silica matrix due to the interaction of the surface hydroxyl groups with sulfosubstituents in the phthalocyanine molecules. Morphological characteristics were determined for the synthesized hybrids. It was shown that the phthalocyanine structure influences the particle size of hybrid obtained. Hybrid materials were examined as catalysts in oxidation model reactions with thiols. The catalytic activity was studied in the temperature range of 298–313 K. The nature of the substituent in the peripheral of metal phthalocyanine has a significant impact on the catalytic activity of the resulting material.

Hybrid materials based on organically modified silica with immobilized boron-dipyrrins (BODIPY) dyes were obtained. Spectral characteristics of the dyes were measured during the matrix formation and in obtained materials. It was stated, that immobilization does not affect the character of the absorption and fluorescence spectra of the dye, but due to the effect of fluorescent molecular rotor observed for meso-substituted BODIPY, the fluorescent quantum yields were found to increase during the matrix sealing. Quantum yield increase is linear for all of the investigated matrices except phenyl-substituted one, where the π-π interactions of the dye molecule with matrix could be observed. This effect could be used for fine control of the matrix formation process and leads to increase of the dye emission in the final material for further practical applications. All obtained hybrid materials were found to be stable upon UV light irradiation, hence immobilization enhance the stability of the dye in comparison with the BODIPY in organic solvents.

The kinetics of the redox reaction of bilirubin by the action of benzoyl peroxide in dimethyl sulfoxide was analyzed. It is shown that the first reaction product is biliverdin, which oxidizes to purpurin and further to choletelin. The kinetic and activation parameters of the oxidation reactions were obtained. A kinetic model of the process was proposed. An assumed route of the reaction is related to the exchange interaction of CH protons of methylene and methine spacers with free radicals in the rate-limiting step with the further destruction of the “ridge-tile” pigment conformation. The mechanism steps are confirmed by quantum-chemical calculations and HPLC. It is found that in organic solvents the end products of bilirubin oxidation are not monopyrrolic derivatives. The data obtained will be useful in constructing antioxidant action models of the pigment.

The surface of silica particles was modified with polyvinyl pyrrolidone (PVP) through solegel process. The different experimental techniques, i.e., thermogravimetric analysis (TGA and DTG), nitrogen adsorption, scanning electron microscopy (SEM), laser diffraction analysis (LDA), fourier transform spectroscopy (FTIR) are used to characterize the pure non-functionalized and functionalized silicas containing different amount of PVP. It was shown that PVP-modified silica samples have well developed porous structure; the values of specific surface area for PVP-modified silicas are in the range of 140 e264 m 2 g � 1 . While the non-functionalized silica shows the low surface area (S BET ¼ 40 m 2 g � 1 ). The BJH analysis showed that PVP can be used as an effective agent to increase an average pore size and total pore volume. The results indicate that PVP functionalized silicas show a potential as effective adsorbents for bilirubin removal compared to other available adsorbents.

Photophysical characteristics of several alkylated dipyrrin Zn(II) complexes in organic solvents were analyzed. Relations between spectral properties of complexes and physical–chemical parameters of solvents were determined with the use of linear regression analysis method. Each solvent parameter contribution in investigated spectral characteristics was estimated. Spectral properties of complexes under study depend on the specific interactions of zinc with the solvent molecules by specific axial coordination. Increasing of alkyl substitution lead to the bathochromic shifts in spectra due to the positive induction effect of alkyl groups.

Grafting with poly(N-vinyl-2-pyrrolidone) (PVP) was used to functionalize silica. The functionalized silicas were characterized by scanning electron microscopy, nitrogen adsorption, energy-dispersive X-ray analysis, Fourier transform spectroscopy, and thermogravimetric analysis. The Barrett–Joyner–Halenda analysis confirmed that PVP-modified silica samples have a mesoporous structure. Bovine serum albumin (BSA) was immobilized onto the surface of PVP-modified silica systems through physical adsorption. Also it was shown that the adsorption capacity of the tested samples depends on the quantity of PVP inside the silica matrix, which confirmed the formation of a specific complex between BSA and PVP. In addition, the effects of pH, time, and concentration on BSA adsorption were investigated. The maximum BSA adsorption capacity was 71.54 ± 2.0 mg/g. The desorption and reusability of all prepared samples were studied as well. PVP-modified silicas are capable of holding more BSA compared to nonmodified silica. ...

Complexes of Pd(II), Cu(II), Ni(II), and Zn(II) with alkylated dipyrrins (Hdpm) were synthesized and characterized by physicochemical and spectroscopic methods. Protolytic dissociation kinetics of these complexes in benzene in the presence of acetic and trichloroacetic acid was studied. A protonated dipyrrin is the reaction product of protolytic dissociation of the complexes in acid solutions. The observed and true dissociation rate constants, as well as activation reaction parameters, were calculated. Kinetic models of the processes are proposed, and the patterns of influence of the ligand nature on dissociation kinetics were determined. The Pd(II) complexes proved to be much more stable than other those of the other metals, according to the results of the kinetic studies. The lability of the complexes strongly depends on the length and position of the alkyl substituent of the ligand. The dissociation of the Ni(II) complex gives a heteroligand complex at low concentrations of acid, but the complex undergoes full protolytic dissociation at higher concentrations of acid. The dissociation of the complex of Cu(II) is an equilibrium process, involving formation of the protonated form of the ligand.

The organic–inorganic composite materials based on mesoporous silica containing bovine serum albumin (BSA) were synthesized using sol–gel method. According to the sol–gel process the surface of silica was modified by amino-groups using 3-aminopropyltrimethoxysilane (APTMS). This modification increased the selectivity to the albumin molecules due to special intermolecular interactions between amino groups of silica and carboxyl groups of BSA. The obtained silicas were characterized by nitrogen adsorption–desorption analysis, fourier transformed infrared spectroscopy, scanning electron microscopy. It was shown that encapsulation of the BSA inside silica matrix leads to the formation of mesoporous materials with high pore diameter (10–14 nm for albumin modified silicas) and a BET surface area equals to 346 ± 17 m 2 /g. The obtained materials were used as adsorbents for selective bilirubin removal. Analysis of adsorption isotherms showed that the adsorption ability to bilirubin depends on the amount of BSA grafted into silica particles. As a result, the amino-modified silica containing 70 mg/g of BSA is characterized by the highest bilirubin adsorption capacity. Thus, the obtained results showed the potential application of these adsorbents in medicine for toxins removal and treatment of hyperbilirubinemia.

Using fluorescence and electronic spectroscopy the interaction of boron-dipyrromethene complex (BODIPY) with bovine serum albumin (BSA) and its bilirubin macromolecular complex (BR·BSA) in aqueous solution was investigated. The interaction of BODIPY is carried out by the static quenching of protein fluorescence and is predominantly hydrophobic and electrostatic in nature. The values of the binding constants were (61.2 ± 2.8) · 103 and (6.51 ± 0.3) · 103 M−1. The interaction of BODIPY with proteins leads to the observed hypso- and bathochromic shift in BODIPY absorption band. Forster resonance energy transfer theory allowed of determing the donor-ligand distance, which were 2.88 and 2.46 nm for BSA and BR·BSA, respectively. Using synchronous fluorescence spectroscopy it was possible to reveal features of BODIPY influence on conformational changes in protein molecules. It was established that BODIPY more effectively interacts with BSA compared to BR·BSA.

The data presented here refer to a research article entitled “Self-Assembled Micellar Clusters Based on Triton-X-family Surfactants for Enhanced Solubilization, Encapsulation, Proteins Permeability Control, and Anticancer Drug Delivery” Solomonov et al., 2019. The present article provides the General Procedure for clusterization of Triton-X-based micelles and the effect of (i) metal ion, surfactant, and chelator concentration on the developed clusters formation, (ii) surfactant-chelator relation change, (iii) metal ion-micelles concertation ratio variation, (iv) metal ion replacement, (v) solvent replacement, (vi) kinetics of clusters formation, (vii) hydrophobic fluorescent dye (Coumarin 6) solubilization in aqueous MCs media, (viii) novel anticancer peptidyl drug synthesis and characterization and (ix) the viability of HeLa cells with and without the presence of drug-free Triton-X-based family MCs. These data provide additional insights useful for understanding all aspects of the micellar clusters formation, optimization, and control. Keywords: Micellar clusters, Surfactants, Triton-X, Self-assembly, Encapsulation, Anticancer drug synthesis, Fluorescence enhancement

This paper demonstrates the possibility of increasing the productivity of crops, while improving the parameters of soil fertility is significantly limited in modern conditions. This trend is associated with low activity of innovation and innovative activities in the field of mineral nutrition of plants. Nevertheless, the existing work in this area clearly indicates the presence of effective recommendations aren’t only to limit the growth of costs for the fertilizer system but to increase its efficiency, besides, to improve the agro-ecological soil parameters.

This article illustrates the new modeled reactor, that allows to change the process of the flow chemical reaction from batch tank to the continuous mode. The stage efficiency form 1 (ideal plug flow, IPF) to 50 stages in a continuous stirrer tank reactor (CSTR) was plotted and illustrated graphically. Moreover, the descriptions and possibilities of the new reactor (V-star) such as: temperature control, numbers of stages, movement-speed of the reactors platform are also shown in this paper work.

The regularities of the kinetic stability of 4,4-difluoro-4-boradiaza-s-indacene (Bodipy) complexes with alkyl and sulfonic substituents to acids and alkalis in aqueous and non-aqueous media were investigated. Bodipy is super resistant to acids in comparison with complexes of d -metals. The rate of dissociation reaction increases with the increasing of protonating mixtures acidity and decreasing of effective charges on ligand nitrogen atoms, the dissociation of the complexes taking place in accordance with the kinetic equation of the second order. A kinetic model of the process was proposed. Kinetic and activation parameters of studied reactions were determined. Using the quantum chemical calculations it was shown that the interactions of acidic protons with fluorine atoms of complex are energetically preferable at the initial stage of Bodipy dissociation than interactions of protons with the nitrogen atoms of ligand. Increasing pH leads to the growth of Bodipy destruction rate. The first step in this case is the alkaline hydrolysis of the complex coordination center. The decay of the ligand anion to mono pyrrolic products occurs at the next stage. Diagrams of transformations corresponding to the experimentally determined rate equation are proposed.

Protolytic dissociation of copper(II) and nickel(II) dipyrrolylmethenates in benzene solutions of acetic acid has been studied. The results have completed the knowledge of kinetics of dipyrrolylmethene complexes dissociation in acidic medium. The effect of the nature of complex forming atom, ligand, and other factors on the complexes kinetic stability has been analyzed.